He tweeted his fans apologetic messages after allegedly smoking marijuana in photos which emerged on TMZ last week, but now a new 'Cutting for Bieber' trend on social media sites has taken the incident to new levels.

The morbid and dangerous mock campaign was sparked by online pranksters urging Bieber fans to self-harm themselves in protest to the controversial images of the pop star. As if he doesn't feel bad enough!

Twitter users and Bieber fans have since posted graphic images of themselves with slashed wrists, surrounded by blades of blood, some unknown to be real or fake.

Justin Bieber has been the subject of a 'sick' Twitter campaign, 'Cut4Bieber' - Splash

The hastag #cut4bieber has now become the top US trend on Twitter, beginning when 4chan users launched a campaign in mock protest to Bieber's alleged marijuana use.

''Lets start a cut yourself for bieber campaign,'' an anonymous user wrote on the site's message board.

''Tweet a bunch of pics of people cutting themselves and claim we did it because bieber was smoking weed,'' they added.

Miley Cyrus backs her pal up by urging trolls to stop the growing trend - Splash

The message board has since been removed, but internet trolls also created fake Twitter accounts, pretending to be teenage girls who were posting images of themselves with cut arms, stating that they were self-mutilating themselves.

Miley Cyrus soon became aware of the trend, weighing in on the subject by begging individuals to stop. ''#cut4bieber? Cutting is NOT something to joke about. There are people who are actually suffering from self-harm, this is so disrespectful.''

Pictures of Justin reportedly smoking the drug were taken on January 2, with the singer seen holding what appears to be a roll-up as he chats with friends inside a hotel room in Newport Beach, California.

He later sent a host of emotional tweets including: ''Everyday growing and learning. trying to be better. u get knocked down, u get up.''